The present invention relates to the improved combustion of natural gas, propane and other gaseous fuels by the use of an innovative burner technology which generates a singular type of flame that combines the advantages and eliminates the disadvantages of current premixed burner technologies.
In the state of the art, the following are accepted by combustion engineers as two separate and distinct types of flames:
A. Blue flames, or open combustion, and PA0 B. Radiant flames, or subsurface combustion.
Simply put, a burner is a physical interface, consisting of one or more orifices, intended to separate and position incoming unburned flammable gas and air from subsequent combustion. Ported burners differ from porous-matrix ones in the location wherein the flame is positioned. Ported burners allow natural gas flames (which are naturally blue in color) to stabilize (and appear) outside of the burner assembly, in the open, whereas with porous burners, flames are stabilized inside the matrix and are not visible, but which impart heat to the matrix, which glows red hot, or radiates.
Prior to about a decade ago, preference for one type of burner technology over the other was determined almost solely by heat-transfer considerations, and not, for example, by any environmental consideration. Increased concern about the impact of natural gas and synthetic fuel combustion on the quality of either the outdoor or the indoor air dramatically changed this situation, especially when the following result was discovered: porous, radiant burners emit only about 10% of the nitrogen oxides, NO.sub.x (NO+NO.sub.2), of ported, blue-flame burners.
This environmentally beneficial attribute did not come without penalty, as it was discovered that port loading (energy released per unit area per unit time) of a typical radiant, porous-matrix burner was only about 2% to about 5%, or less, of that of a ported, blue-flame burner (1,000 vs. 20,000 to 50,000 Btu/in..sup.2 -hr).